Abstract: We present a process model that distinguishes two dimensions of narcissism: admiration and rivalry. We propose that narcissists’ overarching goal of maintaining a grandiose self is pursued by two separate pathways, characterized by distinct cognitive, affective-motivational, and behavioral processes. In a set of seven studies, we validated this two-dimensional model using the newly developed Narcissistic Admiration and Rivalry Questionnaire (NARQ). We showed that narcissistic admiration and rivalry are positively correlated dimensions, yet they have markedly different nomological networks and distinct intra- and interpersonal consequences. The NARQ showed the hypothesized two-dimensional multifaceted structure as well as very good internal consistencies (Study 1, N = 953), stabilities (Study 2, N = 93), and self-other agreements (Study 3, N = 96). Narcissistic admiration and rivalry showed unique relations to the Narcissistic Personality Inventory (NPI), the Big Five and self-esteem, pathological narcissism, and other narcissism-related traits like Machiavellianism, psychopathy, self-enhancement, and impulsivity (Study 4, Ns = 510 - 1,814). Despite the positive relation between admiration and rivalry, the two differentially predicted general interpersonal orientations and reactions to transgressions in friendships and romantic relationships (Study 5, N = 1,085), interpersonal perceptions during group interactions (Study 6, N = 202), and observed behaviors in experimental observations (Study 7, N = 96). For all studies the NARQ outperformed the standard measure of narcissism, the NPI, in predicting outcome measures. Results underscore the utility of a two-dimensional conceptualization and measurement of narcissism.